Commercially, elastomeric materials such as sticky polymers, for example, EPRs and polybutadiene are produced in solution, slurry or bulk processes. So produced, these elastomeric materials are formed into bales and shipped on trucks or rail cars. The bales may or may not be loaded into a shipping container or box for transport. The pallets holding the bales are removed from shipping trucks, cars, and/or containers using forklift trucks employing a hydraulic or pneumatic device. Once the bales are unloaded, they have to be chopped or ground so that they can be fed to a manufacturer's formulating and/or molding process. Thus, the bale form of these elastomeric or rubbery materials involves significant labor and costs to the facility where it is unloaded.
In contrast, recently developed processes, such as gas phase polymerization processes, for example, those developed by Union Carbide Corporation, can produce elastomeric materials combined with a fluidization aid (e.g., sticky polymers such as an ethylene-propylene-ENB terpolymer) which results in a flowable particle that is granular in form upon exiting the polymerization reactor. Hence, the handling problems associated with these gas phase produced materials differ significantly from those or similar elastomers in bale form.
These gas phase produced elastomeric materials can be poured and/or fed via gravity into railroad hopper cars or into trucks for transport. Alternatively, smaller quantities can be placed in bags for shipping. However, it has been discovered that these granular elastomeric materials may exhibit handling problems. It has been found that over time during shipping and/or storage these sticky elastomeric materials have a tendency to compact or consolidate. This makes it difficult for the receiver or user of these materials to unload them and/or feed them into their processes.
Accordingly, there is an on-going need to alleviate or minimize such materials handling problems and to provide a simple, cost-effective means of loading and/or unloading these elastomeric materials.